title: Plasma homocysteine is associated with increased oxidative stress and antioxidant enzyme activity in welders.
abstract: The purpose of this study was to examine the association of vitamin B6 status and plasma homocysteine with oxidative stress and antioxidant capacities in welders. Workers were divided into either the welding exposure group (n = 57) or the nonexposure controls (n = 42) based on whether they were employed as welders. There were no significant differences in vitamin B₆ status and plasma homocysteine concentration between the welding exposure group and the nonexposure controls. The welding exposure group had significantly higher levels of oxidized low-density lipoprotein cholesterol and lower erythrocyte glutathione concentration and superoxide dismutase (SOD) activities when compared to nonexposure controls. Plasma pyridoxal 5'-phosphate concentration did not correlate with oxidative stress indicators or antioxidant capacities in either group. However, plasma homocysteine significantly correlated with total antioxidant capacity (TAC) (partial r(s) = -0.34, P < 0.05) and erythrocyte SOD activities (partial r(s) = 0.29, P < 0.05) after adjusting for potential confounders in the welding exposure group. In the welding exposure group, adequate vitamin B₆ status was not associated with oxidative stress or antioxidant capacities. However, elevated plasma homocysteine seemed to be a major contributing factor to antioxidant capacities (TAC and erythrocyte SOD activities) in welders.
authors.affiliation: Department of Occupational Medicine, School of Occupational Safety and Health, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung 40201, Taiwan.
authors.forename: Hung-Hsin
authors.initials: HH
authors.lastname: Liu
authors.forename: Tung-Sheng
authors.initials: TS
authors.lastname: Shih
authors.forename: Hsin-Ru
authors.initials: HR
authors.lastname: Huang
authors.forename: Shih-Chien
authors.initials: SC
authors.lastname: Huang
authors.forename: Lien-Hsiung
authors.initials: LH
authors.lastname: Lee
authors.forename: Yi-Chia
authors.initials: YC
authors.lastname: Huang
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D003430:Cross-Sectional Studies; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000502:physiology; D013482:Superoxide Dismutase / Q000378:metabolism; D055815:Young Adult
chemical_list: D000975:Antioxidants; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D006710:Homocysteine; D008315:Malondialdehyde; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase